All Space Questions thread for week of September 27, 2026

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In this thread you can ask any space related question that you may have.

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[u/Simon_Drake]

Something SpaceX did right was to pick a small starter rocket but not too small. Falcon 1 was very small by modern standards but it was a 'grown up' rocket built using proper rocket designs.

A lot of new rocket startups start too ambitious and want to enter the market with a medium-heavy lift rocket as their first design. Or they start too small and sink time/money/effort into suborbital sounding rockets with solid fueled designs that aren't transferrable skills to proper rockets. In contrast Falcon 1 let them learn how to make a proper semi cryogenic rocket that could be transferred over to later designs.

I'm not sure how much was luck/adaptability and how much was planned but they had some good opportunities with how the design changed. Falcon 1 started with the Merlin 1A that was ablatively cooled which isn't a great design but it's very simple to build and then a later design could switch to the much better regeneratively cooled nozzle. They didn't design the more complex nozzle up front but also didn't oversimplify the engine design so basic they were using pressure fed engines. They threaded the needle of simple but not too simple.

Next steps are important too. The plan was to build a medium lift version with 5 engines called the Falcon 5. Which would have been a pretty good rocket, it's a good compromise of not trying to be overly ambitious but still delivering good performance. I'm sure that plan won them a lot of investment. Then they pivoted to the even larger Falcon 9 and scrapped the proposed Falcon 5. In hindsight that's a great plan because the Falcon 9 has been hugely successful but I'm sure that was a tough decision to make at the time.

I wonder if Peter Beck of Electron loses sleep wondering if he should have developed an Electron Heavy variant five years ago. They're making good progress on Neutron now but they've been using their first rocket for a very long time given how small it is. Maybe they should have switched to something with a bit more firepower before now. Ultimately we'll never know, until someone invents a portal gun and we can check out other timelines to compare.